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11.
Marja Alestalo’s 《Knowledge, Technology, and Policy》1993,6(1):52-66
Finland has followed the Scandinavian model of the welfare state in which the level of state activism is high, the economic
pressures on the scientific activities are strong, and the left-wing parties and the Center Party have formulated the main
ideas. In the 1970s welfare ideology was adopted in science policy by emphasizing the promotion of socially relevant scientific
activities and the expansion of the university system as a means of effecting equal opportunity. Currently, the trend is toward
a mixed welfare economy. Programs have been prepared in spite of the radical cut in government expenditure, and without a
consideration of the long-term consequences. 相似文献
12.
An X Windows software tool for the construction of faces with a weighted combination of eigenvectors is described. The eigenvectors were extracted from an autoassociative matrix that comprised 100 face images. The program input consists of eigenvectors and sets of weights that describe individual faces and combines these to create face images. The tool creates a panel of buttons that permits the display of individual eigenvectors and the display of an average face as well. Facilities for on-line changes to the intensity of individual eigenvectors can be used to change the appearance of a face. Previously, O’Toole, Abdi, Deffenbacher, and Bartlett (1991) have shown that the intensity of certain individual eigenvectors contains reliable information for determining the sex and race of the face. 相似文献
13.
14.
Silvia A. Bunge Juliane Mauelshagen Thomas J. Carew 《Neurobiology of learning and memory》1997,67(3):259-263
Tail shock induces reflex sensitization inAplysiaand, in parallel, induces a number of modulatory effects in central neurons, such as increased excitability in tail sensory neurons (SNs) and facilitation of synaptic transmission from SNs to motor neurons. Both of these modulatory effects are mimicked by exogenous application of serotonin (5HT) or electrical stimulation of the tail nerve P9. In the present study we examined the activation thresholds for increased excitability and synaptic facilitation induced by either 5HT or P9 stimulation. We found that the concentration of 5HT sufficient to produce a significant increase in excitability produced no significant synaptic facilitation and, conversely, that the intensity of nerve stimulation sufficient to produce significant synaptic facilitation produced no excitability changes. This reversal of relative thresholds for these modulatory effects may reflect the differential access of exogenous 5HT and endogenous 5HT (released by tail nerve stimulation) to the SN cell body and synaptic terminals, respectively. 相似文献
15.
16.
Silvia Mecklenbräuker 《Psychological research》1995,57(3-4):179-191
Previous experiments have shown that the procedure of questioning subjects retrospectively about the input and output status of information (input and output monitoring) is a useful method for assessing the awareness states of subjects during implicit and explicit memory tasks. The main purpose of the present study was to investigate whether the previous findings could be extended to other implicit and explicit memory tasks. We were especially interested in whether differences in input- and output-monitoring performance can be observed when both the implicit and explicit memory tasks are conceptual ones. In a final test phase, the target items from the study phase and new distractor items were presented. In a recognition-like situation, subjects had to decide whether an item had been presented in the study phase (input status), as well as whether they had produced the item in the memory-test phase (output status). In all three experiments judgments about the input status - but only for those items that had been produced in the implicit or in the explicit memory test - were more precise after explicit than after implicit memory testings. This finding was not influenced by the distinction between perceptual and conceptual-memory tasks (Exp. 1), and was obtained under conditions in which the implicit and the explicit memory tasks were both conceptual and differed only in test instructions (Exps. 2 and 3). These results suggest that not only subjects performing a perceptual test of implicit memory, but also subjects in a conceptual implicit test were less aware of using information from a previous study episode than subjects who received memory instructions. It is concluded that requiring judgments about the input status of information is a good method for assessing subjects test awareness and is preferable to the use of a questionnaire (Exp. 3). In contrast, in all three experiments no differences were found with the output-monitoring measure between implicit and explicit test conditions. 相似文献
17.
Frame multiplicity and policy fiascoes: Limits to explanation 总被引:1,自引:0,他引:1
The dynamics of intractability, frame multiplicity and intense controversy not only characterize policy formation struggles, as described by Schön and Rein, but also affect the evaluation of policies and government action. Policy analysts play an important part in the politics of policy evaluation. This article demonstrates that they tend to produce very different explanations for controversial, failing policies. Such differing explanations imply different causal attributions, different allocations of blame, and different lessons for future policy-making. Such differences are not random occurrences; they are embedded in the analytical frames that evaluators use to reconstruct policy processes and to explain their outcomes. It is shown that at least three deep-rooted frames can be reconstructed: fiascoes as failures of public problem solving, fiascoes as institutional imbalances, and fiascoes as system artefacts. One of the great epistemological challenges is how to deal with multiple analytical frames. The final part of the article discusses various strategies. 相似文献
18.
Ken’Ichi Miyazaki 《Attention, perception & psychophysics》1995,57(7):962-970
Two experiments were conducted to examine the effect of absolute-pitch possession on relativepitch processing. Listeners attempted to identify melodic intervals ranging from a semitone to an octave with different reference tones. Listeners with absolute pitch showed declined performance when the reference was out-of-tune C, out-of-tune E, or F#, relative to when the reference was C. In contrast, listeners who had no absolute pitch maintained relatively high performance in all reference conditions. These results suggest that absolute-pitch listeners are weak in relative-pitch processing and show a tendency to rely on absolute pitch in relative-pitch tasks. 相似文献
19.
Françoise Vitu J. Kevin O’Regan Albrecht W. Inhoff Richard Topolski 《Attention, perception & psychophysics》1995,57(3):352-364
The purpose of the present study was to compare the oculomotor behavior of readers scanning meaningful and meaningless materials. Four conditions were used—a normal-text-reading control condition, and three experimental conditions in which the amount of linguistic processing was reduced, either by presenting the subjects with repeated letter strings or by asking the subjects to search for a target letter in texts or letter strings. The results show that global eye-movement characteristics (such as saccade size and fixation duration), as well as local characteristics (such as word-skipping rate, landing site, refixation probability, and refixation position), are very similar in the four conditions. The finding that the eyes are capable of generating an autonomous oculomotor scanning strategy in the absence of any linguistic information to process argues in favor of the idea that such predetermined oculomotor strategies might be an important determinant of eye movements in reading. 相似文献
20.
Frank E. Pollick Shin’ya Nishida Yasuharu Koike Mitsuo Kawato 《Attention, perception & psychophysics》1994,56(1):91-109
We investigated the ability to match finger orientation to the direction of the axis of rotation in structure-from-motion displays. Preliminary experiments verified that subjects could accurately use the index finger to report direction. The remainder of the experiments studied the perception of the axis of rotation from full rotations of a group of discrete points, the profiles of a rotating ellipsoid, and two views of a group of discrete points. Subjects’ responses were analyzed by decomposing the pointing responses into their slant and tilt components. Overall, the results indicated that subjects were sensitive to both slant and tilt. However, when the axis of rotation was near the viewing direction, subjects had difficulty reporting tilt with profiles and two views and showed a large bias in their slant judgments with two views and full rotations. These results are not entirely consistent with theoretical predictions. The results, particularly for two views, suggest that additional constraints are used by humans in the recovery of structure from motion. 相似文献